Winter wheat roots grow twice as deep as spring wheat roots, is this important for N uptake and N leaching losses?

Cropping systems comprising winter catch crops followed by spring wheat could reduce N leaching risks compared to traditional winter wheat systems in humid climates. We studied the soil mineral N (Ninorg) and root growth of winter- and spring wheat to 2.5 m depth during three years. Root depth of winter wheat (2.2 m) was twice that of spring wheat, and this was related to much lower amounts of Ninorg in the 1 to 2.5 m layer after winter wheat (81 kg Ninorg ha-1 less). When growing winter catch crops before spring wheat, N content in the 1 to 2.5 m layer after spring wheat was not different from that after winter wheat. The results suggest that by virtue of its deep rooting, winter wheat may not lead to high levels of leaching as it is often assumed in humid climates. Deep soil and root measurements (below 1 m) in this experiment were essential to answer the questions we posed

The Role of Repetitive Negative Thoughts in the Vulnerability for Emotional Problems in Non-Clinical Children

The current study examined the role of repetitive negative thoughts in the vulnerability for emotional problems in non-clinical children aged 8–13 years (N = 158). Children completed self-report questionnaires for assessing (1) neuroticism and behavioral inhibition as indicators of general vulnerability (2) worry and rumination which are two important manifestations of repetitive negative thoughts, and (3) emotional problems (i.e., anxiety, depression, and sleep difficulties). Results demonstrated that there were positive correlations between measures of general vulnerability, repetitive negative thoughts, and emotional problems. Further, support was found for a model in which worry and rumination acted as partial mediators in the relation between neuroticism and symptoms of anxiety and depression. In the case of sleep difficulties, no evidence was obtained for such a mediation model. In fact, data suggested that sleeping difficulties are better conceived as an epiphenomenon of high symptom levels of anxiety and depression or as a risk factor for the development of other types of psychopathology. Finally, besides neuroticism, the temperamental trait of behavioral inhibition appeared to play a unique direct role in the model predicting anxiety symptoms but not in the models predicting depressive symptoms or sleep difficulties. To conclude, the current findings seem to indicate that worry and rumination contribute to children’s vulnerability for anxiety and depression

The RISAP-study: a complex intervention in risk communication and shared decision-making in general practice

General practitioners (GPs) and patients find it difficult to talk about risk of future disease, especially when patients have asymptomatic conditions, and treatment options are unlikely to cause immediate perceptible improvements in well-being. Further studies in risk communication training are needed. Aim:1) to systematically develop, describe and evaluate a complex intervention comprising a training programme for GPs in risk communication and shared decision-making, 2) to evaluate the effect of the training programme on real-life consultations between GPs and patients with high cholesterol levels, and 3) to evaluate patients' reactions during and after the consultations. Methods/Design The effect of the complex intervention, based around a training programme, will be evaluated in a cluster-randomised controlled trial with an intervention group and an active control group with 40 GPs and 280 patients in each group. The GPs will receive a questionnaire at baseline and after 6 months about attitudes towards risk communication and cholesterol-reducing medication. After each consultation with a participating high cholesterol-patient, the GPs will complete a questionnaire about decision satisfaction (Provider Decision Process Assessment Instrument). The patients will receive a questionnaire at baseline and after 3 and 6 months. It includes questions about adherence to chosen treatment (Morisky Compliance Scale), self-rated health (SF-12), enablement (Patient Enablement Instrument), and risk communication and decision-making effectiveness (COMRADE Scale). Prescriptions, contacts to the health services, and cholesterol level will be drawn from the registers. In each group, 12 consultations will be observed and tape-recorded. The patients from these 24 consultations will be interviewed immediately after the consultation and re-interviewed after 6 months. Eight purposefully selected GPs from the intervention group will be interviewed in a focus group 6 months after participation in the training programme. The process and context of the RISAP-study will be investigated in detail using an action research approach, in order to analyse adaptation of the intervention model to the specific context. Discussion This study aims at providing GPs and patients with a firm basis for active deliberation about preventive treatment options, with a view to optimising adherence to chosen treatment. Trial registration ClinicalTrials.gov Protocol Registration System NCT0118705

The ancestral role of ATP hydrolysis in type II topoisomerases: prevention of DNA double-strand breaks

Type II DNA topoisomerases (topos) catalyse changes in DNA topology by passing one double-stranded DNA segment through another. This reaction is essential to processes such as replication and transcription, but carries with it the inherent danger of permanent double-strand break (DSB) formation. All type II topos hydrolyse ATP during their reactions; however, only DNA gyrase is able to harness the free energy of hydrolysis to drive DNA supercoiling, an energetically unfavourable process. A long-standing puzzle has been to understand why the majority of type II enzymes consume ATP to support reactions that do not require a net energy input. While certain type II topos are known to ‘simplify’ distributions of DNA topoisomers below thermodynamic equilibrium levels, the energy required for this process is very low, suggesting that this behaviour is not the principal reason for ATP hydrolysis. Instead, we propose that the energy of ATP hydrolysis is needed to control the separation of protein–protein interfaces and prevent the accidental formation of potentially mutagenic or cytotoxic DSBs. This interpretation has parallels with the actions of a variety of molecular machines that catalyse the conformational rearrangement of biological macromolecules